tethered jailbreak 5.1 atv2

I read that there is a thetered jalbreak for 5.1 9B179b,  is this true?

i tried to downgrade from 5.1 to 4.4.2  but it’s tricky i think, it can made my atv2 broke?

 

I do believe there is a tethered jailbreak which only provides SSH access only through redsn0w. But sorry if downgrading to 4.4.2 is “tricky” then wait for a more viable solution.